BIOL 1209 Lecture : BIO 1209 Notes
Document Summary
Decreased dependence on water: presence of vascular tissues increase in size/height, 2. Life cycle: sexual reproduction via alternation of generations, size of sporophyte vs. gametophyte, 3. The rest are invertebrates: 75% of all described animals are insects, trends of increasing complexity in the following characteristics, 1. Others include singles vs. multiple segments and hydrostatic vs. external vs. internal skeletons: symmetry (increasing complexity going from 1. - 3. , 1. 2 equal halves any which way you cut it through the middle. Can divide in half only one way and get equal sides left and right sides. Very low complexity: two tissue layers. Allow for gastro vascular cavity to form. Organisms can now get bigger because they can consume larger foods and thus obtain more energy: three tissue layers. Middle layer results in new structures not associated with covering or digestion such as nerves, blood vessels: body cavity development, no body cavity.
